With the rapid advancement of nanotechnology, techniques for generation and measurement of micro/nanonewton forces are widely applied in various fields of science and industry. In biotechnology, an atomic force microscope (AFM) is used to measure the interaction forces between biological molecules. In material science, an instrumented indentation system is used for determining the elastic modulus and hardness of material. In fundamental science, Casimir force is measured by the AFM with piconewton resolution. Although measurements of forces at nano/piconewton scale are ordinary among these applications, the lowest “International System of Units” (SI) traceable force standard provided by the National Metrology Institutes (NMIs) is only a few micronewtons. To meet the need for a traceable force measurement at micro/nano/piconewton level, several NMIs have developed new force standard systems for SI traceable force realization at micro/nanonewton level. The NIST Microforce Project has developed an electrostatic force balance (EFB), and demonstrated SI force realization of forces below 5 micronewtons (A) with a resolution of a few nanonewtons (nN). The force is electrostatic and linked to electrical unit standards and the Josephson and quantized Hall effects. KRISS has established a nano-force calibrator based on a precision microbalance, which is designed for the calibration of the spring constant of the AFM cantilever. In addition, KRISS is also developing a controllable, piconewton-range ultra-low-force realization based on a macroscopic quantum phenomenon: magnetic flux quantization in a superconducting annulus. The PTB group has constructed a new nanonewton-force standard facility for measuring forces below 10 μN with a piconewton-scale resolution. The NPL group has developed a low force balance in which the force is electrostatic and realized by a dielectric and two metal electrodes. In the Center for Measurement Standards (CMS), Industrial Technology Research Institute (ITRI), a torsion pendulum facility is built for measuring forces below 20 nN with a piconewton-scale resolution. The apparatus is capable of comparing forces produced from three methods, namely the radiation pressure force, the electrostatic force and the gravitational force.